Method of hardening a surface of a golf club head

ABSTRACT

A method of hardening a surface of a golf club head includes the steps of positioning a golf club head in a chamber filled with a protecting gas, and irradiating a predetermined metallic surface area of the golf club head with a light beam from a light generator so as to heat-treat and harden the predetermined area of the golf club head.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a method of hardening a surface of a golf club head, more particularly to a method of hardening a surface of a golf club head using a light beam.

2. Description of the Related Art

It is necessary to increase hardness of a specific area of a golf club head for the striking function. One of conventional methods available for achieving this object is to apply a layer having a relatively high hardness on a surface of the golf club head by electroplating, physical vapor depositing, or chemical vapor depositing. However, since bonding strength between the applied layer and the surface of the golf club head may degrade after a period of use, the applied layer is liable to be peeled from the surface of the golf club head.

Another conventional method for improving the hardness of the golf club head involves heat treatment of the golf club head in a furnace. However, since such a heat treatment is used to increase the hardness of the whole golf club head, it cannot be used for increasing the hardness of a specific area of the golf club head, such as a striking area of the golf club head, which is usually desirable in the art.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a method of hardening a surface of a golf club head in a controllable manner.

Accordingly, the method of this invention includes the steps of positioning a golf club head in a chamber filled with a protecting gas, and irradiating a predetermined metallic surface area of the golf club head with a light beam from a light generator so as to heat-treat and harden the predetermined area of the golf club head.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which:

FIG. 1 is a flow chart of the preferred embodiment of a method of hardening a surface of a golf club head according to this invention;

FIG. 2 is a perspective view illustrating how a predetermined surface area of the golf club head is hardened according to the preferred embodiment; and

FIG. 3 is an enlarged perspective view of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, the preferred embodiment of a method of hardening a surface of a golf club head according to this invention is shown to include the steps of:

A) Preparing a Golf Club Head:

In this preferred embodiment, a golf club head 2 to be treated is an iron head made of titanium alloy. Other suitable materials, such as aluminum alloy, carbon steel, stainless steel, or the like, can be used for making the golf club head 2. Additionally, other kinds of the golf club head 2, such as a wood head or a putter head, can also be treated by the method of this invention as long as the portion of the golf club head 2 to be treated is metallic.

B) Positioning:

The golf club head 2 is positioned in a hardening device 3, which includes a chamber 31, a gas supplying unit 32 for supplying a protecting gas into the chamber 31, a stage 33 mounted in the chamber 31 for positioning the golf club head 2 thereon, and a light generator 34 mounted outside the chamber 31 for generating a light beam 341. The chamber 31 is provided with a glass window 311 that permits transmission of the light beam 341 from the light generator 34 to the golf club head 2 therethrough. The gas supplying unit 32 includes a gas reservoir 321 and a gas supplying tube 322 interconnecting the gas reservoir 321 and the chamber 31 for supplying the protecting gas from the gas reservoir 321 into the chamber 31 so as to protect and cool the golf club head 2. The protecting gas suitable for this invention is an inert gas, such as nitrogen, helium, or argon. The stage 33 is movable relative to the chamber 31 in one of linear and rotary directions.

C) Irradiating:

Referring to FIGS. 2 and 3, the light beam 341 generated by the light generator 34 is a high-energy light beam having a profile resembling a strip or a cylinder, and is transmitted to the golf club head 2 through the window 311. The traveling path of the light beam 341 on the golf club head 2 can be controlled through movement of the light generator 34 relative to the stage 33.

In the preferred embodiment, the light generator 34 is a high power laser diode system having a power ranging from 2000 to 5000 watts, and generates a laser light beam having a wavelength ranging from 808 to 940 nm. The illuminating area of the laser light beam ranges from 2.25 mm² to 180 mm². When the laser light beam has a profile resembling a strip, the illuminating area thereof ranges from 1.5×1.5 mm² to 9.0×20 mm². In addition to the laser light beam, another light beam useful in this invention is an infrared light beam.

The light generator 34 used in this invention can be a solid-state laser system (such as a Nd-YAG laser system or a Nd-Glass system), or a gaseous laser system (such as a carbon dioxide laser system, a helium-neon laser system, or an argon laser system).

A predetermined metallic surface area of the golf club head 2 is irradiated with the light beam 341 from the light generator 34 so as to heat-treat and harden the predetermined area of the golf club head 2. The irradiating treatment is usually performed at an ambient temperature. The temperature of the predetermined metallic surface area of the golf club head 2 treated by the irradiation can be monitored using a temperature sensor, such as an infrared sensor. The hardness and the depth of the predetermined metallic surface area of the golf club head 2 to be treated can be controlled by the operating conditions, such as the power and the moving velocity of the light generator 34, the heating temperature, the heating time, etc. The operating conditions suitable for the specific requirements for the golf club head 2 to be treated can be selected by the skilled artisan, and will not be described in detail herein. Additionally, the cooling rate of the golf club head 2 can be controlled by adjusting the gas supplying rate of the gas supplying unit 32.

In view of the aforesaid, the predetermined metallic surface area of the golf club head 2 can be treated via irradiation with the light beam 341 to increase the hardness of the area while maintaining the original physical properties of the non-treated area of the golf club head 2. Furthermore, the peeling problem encountered in the prior art can be avoided by this invention.

It should be noted that, in addition to the direct treatment of the surface of the golf club head 2, the method of this invention can be performed to heat-treat and harden an additional layer applied on the golf club head 2.

While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements. 

1. A method of hardening a surface of a golf club head, comprising the steps of: positioning a golf club head in a chamber filled with a protecting gas; and irradiating a predetermined metallic surface area of the golf club head with a light beam from a light generator so as to heat-treat and harden the predetermined area of the golf club head.
 2. The method as claimed in claim 1, wherein the light beam is an infrared light beam.
 3. The method as claimed in claim 1, wherein the light beam is a laser light beam.
 4. The method as claimed in claim 1, wherein the light beam has a profile resembling one of a strip and a cylinder.
 5. The method as claimed in claim 1, wherein the golf club head includes a metal selected from the group consisting of aluminum alloy, titanium alloy, carbon steel, and stainless steel.
 6. The method as claimed in claim 1, wherein the protecting gas is selected from the group consisting of nitrogen, helium, and argon.
 7. The method as claimed in claim 1, wherein the light generator has a power ranging from 2000 to 5000 watts.
 8. The method as claimed in claim 1, wherein the light beam has a wavelength ranging from 808 to 940 nm. 